What is the relationship between kg wt and Newtons through dimensional analysis?

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SUMMARY

The relationship between kilogram weight (kg wt) and Newtons (N) is defined by the equation 1 kg wt = 9.81 N, where kg wt represents the force required to accelerate a mass of 1 kg at 9.81 m/s² due to gravity. Dimensional analysis confirms that kg wt is a unit of force, equivalent to 9.81 N. This relationship is established through the formula W = ma, where W is weight, m is mass, and a is acceleration due to gravity. The kilogram-force is an arbitrary unit, similar to the pound-force, which is defined as 1 lb = 4.448 N.

PREREQUISITES
  • Understanding of Newton's second law of motion (W = ma)
  • Familiarity with units of force, specifically Newtons and kilogram-force
  • Basic knowledge of dimensional analysis
  • Concept of gravitational acceleration (approximately 9.81 m/s² on Earth)
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  • Study the concept of dimensional analysis in physics
  • Learn about the differences between mass and weight in physics
  • Explore the implications of gravitational acceleration on force calculations
  • Investigate other units of force and their conversions, such as pounds to Newtons
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Students of physics, educators teaching mechanics, and professionals in engineering or physical sciences who need to understand the relationship between mass, weight, and force.

sphyics
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i know its a unit for force... I'm intrigued by the relation 1kgwt=9.8N?

by dimensional analysis

L.H.s [M2L1T-2 {since wt=kgm/s2}
R.H.S [M1L1T-2
i understand I'm wrong somewhere, but I'm not able to figure it out, so pls help me :)

Also how to get the relation between both.( think 9.8 is the contribution of 'g')
 
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sphyics said:
i know its a unit for force... I'm intrigued by the relation 1kgwt=9.8N?

by dimensional analysis

L.H.s [M2L1T-2 {since wt=kgm/s2}

You interpreted kg wt as mass*weight. A kilogram weight is a unit of force. Specifically, it is the force needed to make a mass of 1 kg accelerate by 9.80665 m/s2.
 
D H said:
You interpreted kg wt as mass*weight. A kilogram weight is a unit of force. Specifically, it is the force needed to make a mass of 1 kg accelerate by 9.80665 m/s2.
yes

and how to get the relation 1kgwt=9.8N mathematically.
 
You can't derive it. The kilogram-force (sometimes called the kilogram-wt) is defined as the force needed to make a one kilogram of mass accelerate by 9.80665 m/s2.
 
sphyics said:
how to get the relation 1kgwt=9.8N mathematically.

1 kgwt means the "weight of a mass of 1 kg on earth". So:

W = ma = (1 kg)(9.81 m/s²) = 9.81 N = 1 kgwt

kgwt is an arbitrary defined unit for force, just like 1 lb = 4.448 N
 
jack action said:
1 kgwt means the "weight of a mass of 1 kg on earth". So:

W = ma = (1 kg)(9.81 m/s²) = 9.81 N = 1 kgwt

kgwt is an arbitrary defined unit for force, just like 1 lb = 4.448 N

Thanks for ur explanation now i understand
 
I do not have a good working knowledge of physics yet. I tried to piece this together but after researching this, I couldn’t figure out the correct laws of physics to combine to develop a formula to answer this question. Ex. 1 - A moving object impacts a static object at a constant velocity. Ex. 2 - A moving object impacts a static object at the same velocity but is accelerating at the moment of impact. Assuming the mass of the objects is the same and the velocity at the moment of impact...

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